'1979 200 Evinrude Starter Overheating and Raw Blow-by?

I'm new to this forum and this is my first post. I have rebuilt a 1979 Evinrude 200 HP with pieces and parts from ebay and other sources. The boat starts right up and runs great (5250 RPMs), all day, no problems...except...

Problem number 1: There seems to be an extreme amount of unburnt fuel that dumps into the water at idle, at normal running RPMs and at OFF. What I mean is that even when the motor is turned off, unburned oil and fuel (as I pre-mix in the gas tank 50:1 (synthetic)) fills the water like an oil slick. It seems to be coming from the prop area? It is literally as if the Exon Valdez had just left the area. I've tried running a six gallon tank with non-synthetic to see if it was the oil, same results, however. No unburnt fuel under the cowling however; just exhausting out. FYI- I've got great compression on all 6.

Problem number 2: After a few hours of running (that's running, not starting, as the boat starts right up), the starter seems to actually overheat and won't start the boat. I am talking about for hours. It takes hours to cool it down. This is when I pull out my trusty back-up starter and carefully change them out with an oven mitt. The boat starts right up and off I go, slicking up the lake with my unburnt fuel problem.

Any help with either of these problems is greatly appreciated. Thanks...

Re: '1979 200 Evinrude Starter Overheating and Raw Blow-by?

Do you have the original 1 5/16" carbs from a 200 on the powerhead? Is it a true 200 block? It could be running rich at idle. Amy unburned fuel will coat the exhaust leg in the midsection and it can wind up floating up from the prop in the water. You would probably also see signs/black sooty spots on the driveway when it is parked there. Your starter issue is unusual. Something may be causing the starter to stay running as you are boating. Perhaps the solenoid is sticking or the key switch is shorting it out. The starter can stay running with the bendix retracted and you might not know.

Re: '1979 200 Evinrude Starter Overheating and Raw Blow-by?

Yes, original carbs (rebuilt) on the original block. I keep it in a slip in South Carolina and so I haven't had it in the driveway. I'll look into leaning up the carbs and see what happens. Good point about the solenoid. I'm going to run the back-up starter this weekend as the primary and see if the results are the same.

Thanks.

Re: '1979 200 Evinrude Starter Overheating and Raw Blow-by?

sounds to me like the float level may be too high dumping fuel when engine shuts off

Re: '1979 200 Evinrude Starter Overheating and Raw Blow-by?

If it is a stock block and stock carbs, the carbs should be setup ok as they are. You are lugging this engine when you run top rpm at only 5200-it's probably slow out of the hole, too. This is a high port block, rated to run at 5750 by the factory. Mine made strong power right up to 6000 without a whimper. Lugging the engine will cause the engine to dump in more fuel and it may not burn as well-can cause some of the issues you noted. Suggest you reprop it. Also check to be sure both heads come up to normal operating temps at idle 145-155. If it either heads run cold, you won't get proper combustion and it will tend to smoke more.